Safety assessments on the adda river crossing in S. Giacomo di Teglio

As part of the safety management of the “Sentiero Valtellina,” the cycle-pedestrian footbridge over the Adda River in S. Giacomo di Teglio (SO), after 12 years of service, was subjected to structural performance maintenance checks.

The Comunità Montana Valtellina di Tirano commissioned Foppoli Moretta and Associati to carry out a diagnostic campaign to assess the overall condition of the deck, the tension state of the stay cables, the integrity of welds between metallic components, and the condition of pins, rods, and anchorages.

The diagnostic activities, entirely based on non-destructive testing, were specifically aimed at acquiring structural information that was either not detected or not controlled during the original construction of the bridge.

A comprehensive investigation was therefore conducted using magnetic and ultrasonic techniques on the metallic components, and the dynamic behavior of each stay cable was measured to determine its actual tension state.

The methods and instrumentation employed today are significantly more advanced than those available at the time of the bridge’s construction, and the results of this campaign contribute to a more complete understanding of the structure.

The results allow a comparison between the bridge’s current condition and its original design, highlighting any potential need for timely remedial interventions.